IGNEOUS ROCKS
-One of the three main rock types.
-Igneous rock is formed by magma being cooled and becoming solid.

-melting is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition.
-i
gneous rocks make up approximately 90% of the upper part of the Earth's crust
-they are the oldest type of rock. The word igneous comes from the greek word for fire.
-Igneous rocks are classified according to mode of occurrence, texture, mineralogy, chemical composition, and the geometry of the igneous body.
-The slow cooling formed rocks with large crystals. Granite is an example of a rock that cooled slowly and has large crystals.
-Igneous rocks form in three main places: where lithospheric plates pull apart at mid-ocean ridges, where plates come together at subduction zones and where continental crust is pushed together, making it thicker and allowing it to heat to melting.

WHERE IGNEOUS FORM:
Igneous rocks form in three main places:
where lithospheric plates pull apart at mid-ocean ridges.
where plates come together at subduction zones.
where continental crust is pushed together, making it thicker and allowing it to heat to melting.


TYPES:

Intrusive-
-when they form below the earths surface.
-coarse grained
-magma cools slowly

Extrusive-
- when they form on the earths surface.
- fined grained
- magma cools quickly





PICTURES:


igneous.jpg


Composition
Mode of occurrence
Felsic
Intermediate
Mafic
Ultramafic
Intrusive
Granite
Diorite
Gabbro
Peridotite
Extrusive
Rhyolite
Andesite
Basalt
Komatiite


Essential rock forming silicates

Felsic
Intermediate
Mafic
Ultramafic
Coarse Grained
Granite
Diorite
Gabbro
Peridotite
Medium Grained


Diabase

Fine Grained
Rhyolite
Andesite
Basalt
Komatiite


==Some Common Igneous Rocks==
===Name===
===Image===
===Color===
===Texture===
Granite
external image granite.jpg
Pink/Gray
Intrusive
Gabbro
external image gabbro.jpg
Dark Gray to Black
Intrusive
Rhyolite
external image rhyolite.jpg
Light Pink or Gray
Extrusive
Basalt
external image basalt.jpg
Dark Gray to Black
Extrusive
Obsidian
external image obsidian.jpg
Usually Dark Colored
Extrusive
Scoria
external image scoria.jpg
Dark Colored
Extrusive




WEBSITES:

http://en.wikipedia.org/wiki/Igneous_rocks


SEDIMENTARY ROCKS

Vocabulary:
sediments
- small pieces of rock that are moved and deposited by water, wind, glaciers, and gravity.
lithification - the physical and chemical processes that transform sediments into sedimentary rocks. ( lithy comes from the Greek word lithos, which means stone.)
cementation - occurs when mineral growth glues sediment grains together into solid rock.
bedding - the primary feature of sedimentary rocks horizontal layering.
graded bedding - bedding in which the particle sizes become progressively heavier and coarser toward the bottom layers.
cross bedding - formed as inclined layers of sediment are deposited across a horizontal surface,
erosion - the removal and transport of sediment
Facts:
-The formation of sedimentary rocks begins when weathering and erosion produce sediments.

-Sediments range in size from huge boulders to microscopic particles.
-Chemical weathering occurs when the minerals in a rock are dissolved or otherwise chemically changed.
-When less stable minerals are chemically broken down, the more-resistant grains are broken off of the rock as smaller grains.
-After rock fragments and sediments have been weathered out of the rock, they often transported to new locations through the process of erosion.






PICTURES:


coal.jpg





METAMORPHIC ROCKS
- heat and pressure creats metamorphic rocks
- goes through physical and chemical changes
- formed deep in the Earths crust
- make up a huge part of the Earths crust
- examples of metamorphic rocks are: gneiss, slate, marble, schist, and quartzite
- layering in a metamorphic rock is called foliation
- when a rock is not layerd it is nonfloliated
- metamorphic rocks have a grain size anywhere from fine to coarse
- the texture in metamorphic rocks are banding and mineral alignment
- regional, is a type of metamorphism which is wen the heat and pressure increase



PICTURES:


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ROCK CYCLE:


-
the rock cycle describes the transistions threw the three rock types, igneous, sedimentary, and metamorphic

- the rock cycle is an illustration that explains how the 3 rock types are related to each other and how processes change from one type to another over time



PCITURES:

the rock cycle
external image EFCycleP2.gif
external image Igneous%20Rocks.jpgigneous rock formation